摘要:
A data processing terminal device is on-line connected to a host computer and records on journal paper journal data obtained as a result of communication with the host computer. Data is encrypted, and encrypted data is exchanged between the terminal device and the host computer. An IC card connected to the terminal device receives the encrypted data from the host computer, decrypts the data, modifies it and records the data on a recording medium. The terminal device records decrypted data on a journal paper. By comparing the journal data with it's modified data recorded on the IC card, journal data alteration can be easily detected.
摘要:
A data processing terminal device is on-line connected to a host computer and records on journal paper journal data obtained as a result of communication with the host computer. Data is encrypted, and encrypted data is exchanged between the terminal device and the host computer. The encrypted journal data received by the terminal is decrypted and printed on a journal paper, then modified and stored in a PROM. By comparing the journal data with the modified data, journal data alteration can be easily detected.
摘要:
A data processing terminal device is on-line connected to a host computer and records on journal paper journal data obtained as a result of communication with the host computer. Data is encrypted, and encrypted data is exchanged between the terminal device and the host computer. The encrypted journal data is printed together with the normal journal data on the journal paper. The algorithm used to encrypt the data is stored on an ic card issued to the user and updated periodically. By comparing the journal data with its encrypted data, journal data alteration can be easily detected.
摘要:
A card contains an IC chip having a CPU, a memory, etc. When the card is inserted into a terminal device, it is connected to a host computer. Under this condition, the data in the memory of the IC card is processed by the host computer. The memory is manufactured in such a way that the memory area is segmented into a plurality of zones. An access controller for the memory is provided in the IC chip. In issuing the card, the access condition of each zone (for example, an assortment of access people and/or a type of access terminal) is programmed into the access controller by a card issuer.
摘要:
An IC card comprises CPU, PROM for storing programs, and RAM for storing the results of arithmetic operations. PROM stores a table on which the names of specific programs are registered. RAM has execution counters which counts up each time each program is run so that the number of times the specific program is run is memorized. Prior to the running of each program by CPU, it is judged whether or not the program is a specific one. If it is the specific program, the execusion counter counts up. When the count value of the execution counter is above a predetermined value, the running of the specific program is prevented.